Among the neuronal and peripheral cell receptors that bind the neurotransmitter acetylcholine (ACh), are the muscarinic receptors. There are reportedly five subtypes classified as M1 through M5, of which the M1 and M2 have been implicated in the etiology of such medical conditions as Parkinson's disease, cardiac disorders and gastrointestinal disorders. It has been suggested that compounds capable of interfering with the action of acetylcholine at these receptors, would be useful to treat these conditions. However, the tendency for ligands to bind indiscriminately to various other receptor types, such as serotonin and dopamine receptors has made difficult the development of drugs that are muscarinic M1/M2 receptor-selective. It would nevertheless be desirable to provide such a compound, particularly so that side effects are minimized during treatment of the conditions noted above.
It is an object of the present invention to provided a compound having muscarinic M1/M2 receptor affinity.
It is an object of the present invention to provide a compound having an improved muscarinic M1/M2 receptor selectivity profile.
It is a further object of the present invention to provide a pharmaceutical composition comprising a compound of the present invention, as active ingredient.